Depending on the talent available, a manager will opt for a certain formation. The 4-5-1, which we will explore here, is a common choice for perceived "weaker" teams or for coaches who prefer the defensive side of the game.

Bleacher Report brings you an in-depth look at the system along with examples, both good and bad.

The basics

Here's you basic outline for the 4-5-1 formation.

What's the difference between this and 4-3-3? Not a lot in terms of shape, but they differ greatly with regard to the mentality and tendencies of the team.

It's essentially a solid back four, one exclusive holding midfield charged with breaking up play and nothing else, quick wingers and a very hard-working lone striker.

Despite the presence of three central midfielders, it's not typically possession-based. It has a counterattacking outlook with an emphasis on quick, direct balls forward.

Let's take a look at some specific instances in order to outline how it's used.

Case study: Jose Mourinho's Chelsea

Mourinho is and always will be a manager who puts winning first. He doesn't dabble with possession figures or fancy formations—Real Madrid's typical dominance on the ball is a product of him assembling excellent players, not an emphasis on retention strategies.

To win at Chelsea, the Portuguese tactician decided a solid outlook was best and kept it very, very tight.

He used the famous Claude Makelele in his anchor midfield spot, and the Frenchman did a sublime job of harassing, tackling, man-marking and laying simple balls off to his teammates once possession was won.

Full-backs Ashley Cole and Paulo Ferreira were rarely encouraged to venture forward to the same extent they do so now, while DidierDrogba was required to do a double shift up front on his own.

With players slow to move forward and support, the onus was on the Ivorian to hold the ball up even longer than usual to move his team up the field.

Mourinho crafted a system where he had at least four players defending no matter what the circumstances were and utilised Drogba's ridiculous physical prowess to make up for a lack of numbers up top.

It was safe, effective yet potent too. So many 1-0 wins, but who cares when you're winning trophies?

Shaun Botterill/Getty Images

Case study: Alex McLeish's Aston Villa

The difference between McLeish and Mourinho is that the latter used this formation that was right for the personnel and right for the club, while the former used it because he is defensive and inflexible.

The 4-5-1 put together at Villa Park during the 2011-12 season reeked of a lack of faith in player ability and placed an onus on grinding things out.

StiliyanPetrov was his Makelele and was rather effective, leading the English Premier League in interceptions per game until he was unfortunately stricken with illness.

With no other pure holding midfielder on the books, McLeish would have been wise to switch formations, but he didn't. He tried a host of players there instead, including centre-back Ciaran Clark and energetic dynamo Chris Herd.

Villa played the same long balls that Chelsea did, only to the significantly smaller target of Darren Bent—a player who prefers a through-ball to run onto down the channels.

Dean Mouhtaropoulos/Getty Images

Conclusion

It's easy to brand the 4-5-1 as a counterattacking, safe formation.

Many believe it is exclusively negative, but Mourinho begs to differ. He looked at his squad and deduced the correct system to use. In that case, it was the 4-5-1.

That's what sets great managers apart, and the 4-5-1 has almost come to serve as a virtual litmus test in this respect.